It probably would not make much of a difference with 
respect to reduced insurance rates whether the group 
was a union or an association. Either way there would be a 
larger number of people participating in the group.
However, with  respect to negotiation of fees  an association 
may not have the same solidarity as an union, and may not
speak with the same singularity.
to post a reply: 
login - or - 
register